Bichrome ribbon mechanism for computing machines



Aug- 13 1935 w. A. ANDERSON 2,011,310

BICHROME RIBBON MEGHANISM FOR COMPUTING MACHINES Filed Nov. 13, 1930 Patented Agg. 13, 1935 UNITED STATES PATENT OFFICE BICHROME RIBBON MECHANISM FOB COMPUTING MACHINES Walter A. Anderson, Rockford, Ill., assignor, by

mesne assignments, to Underwood Elliott Fisher f Company, New York, N. Y., a corporation of Application November 13, 1930, Serial No. 495,313

` 8 Claims. (Cl. 35-60) This invention has for.its object the provision of simple and reliable means for controlling the movements of a bichrome ribbon so that debit imprints (i. eedebit items and debit totals) may '5 be made in one color, and credit imprints (i. e.

substracted items and overdrafts or negative totals) may be made in the other color, said means being capable of modification so as to effect the printing of overdrafts or negative totals only in said other color.

' In the accompanying drawing:

Figure 1 is a fragmental longitudinal'vertical sectional'view illustrating one embodiment o f my invention. The parts are shown in the debit position.

` Fig. 2 is a fragmental plan view.

Figs. 3 and 4 are detail views of a detent comprised in the mechanism.

Fig. 5 is a detail view of the lever 21.

For a general understanding of one form of computing and printing machine in which my invention may be used, reference may be made to British Patent No. 223,866 granted to Rockford Milling Machine Company and French Patent No. 625,678 issued to The Sandstrand Corporation.l These patents will afford a detailed knowledge of the machine partially illustrated in the present drawing. Y

'I'he numeral 3 denotes a combined type bar and counter-actuating member which is mounted for vertical reciprocation, there being one lsuch .member for each numerical order. Each of the members 3 is raised into printing position by means including a lever 4 which is pivoted on the axis 5 and has a pin-and-slot connection with its member 3. The members 3 are returned to their initial position by means including a universal bar 5 which is arranged to overlie the levers l, the ends of said bar being attached to two levers 1 which swing on the axis 5 in every cycle of operations of the machine.

A bichrome ribbon 9 is arranged to be raised and lowered by means including two members 9 located at opposite sides of the group of type bars 3. Only one of the members 9 is shown in the present drawing. The members 9 are guided for vertical movement by any suitable means, as, for example, guide studs I0 xed in the machine frame and guide slots Il in the members 9.

The means for raising and lowering the members 9 comprises a pin I2 carried by each of the levers 1 in position to engage yieldable projections carried by the members 9. 'Ifhe projections carried by one of the members 9 are like those carried by the other. The lower projection I3 is pivoted upon the member 9 at Il. The upper prolection I5 is pivoted to the member 9 at II.y A contractile coiled spring I1 yieldingly holds the projections in normal position, the action of the spring being limited by a stop I8 on the member 9. The pins I2 are arranged to move up and down within the space between the members I3 and I5. The spring I1 allows the members I3 and I5 to yield when the members 9 are held against movement.

The means for controlling the action of the pins I2 on the members 9 comprises two lugs I9, one vsuch lug being fixed to the lower portion of each of the members 9, each lug being arranged to engage either of two shoulders on a. latch 20 which is pivoted in the machine frame at 2 I. Although only one `latch is shown in the drawing, there is one adjacent to each of the members 9, the latches being rigidly connected to swing in unison by means of two crossbars 22. The shoulders above alluded to are numbered 23 and 2l. When the lugs I9 are in alinement -with the shoulder 23, the members 9 are prevented from rising to lift the ribbon 8 beyond the position where it will present a certain field, say, the blue field, to the printing devices. When the lugs I9 are in alinement with the shoulder 24 the members 9 are free to be lifted by engagement of the pins I2 with the projections I5 so as to present the other field, as, for example, the red field, to the printing devices.

The means for operating the latches 20 comprises a link 25 which controlsa function of the machine, as, for example, by determining the sign of the accumulation. It may be assumed in this instance that the link 25 determines whether addition orl subtraction shall occur. When the link 25 is moved rearwardly by means such, for example, as that disclosed in the before-mentioned French patent, the machine is conditioned for i the subtraction of items or for the taking of a negative total. The forward end of the link 25 is pivoted at 26 to a lever 21 which is pivoted in the machine frame at 28. A lug 29 attached to the stem of the subtraction key 3l) overlies the lever 21. Thus it will be seen that when the subtraction key is depressed the link 25 will be pushed rearwardly to condition the machine for the subtraction of items or for the taking of a negative total.

The latches 20 are connected to the link 25 by means of a tension spring 3|. One end of said spring is connected to a lug 32 rigidly secured to the link 25. The other end of the spring 3| is attached to an anchor pin 33 on the right-hand latch 20. Normally the spring 3| holds the end of said latch against the lug 32, as shown in Figs. 1 and 2.

It will be seen that when thesubtraction link 25 is moved rearwardly into subtraction or negativetotal position the latches will be moved rearwardly so as to withdraw the shoulder 23 from engagement with the lugs IS-and place the shoulders 24 in position to limit upward movement of the members 9. If it be desired that subtracted items as well as negative totals be printed in a distinctive color, say red, the latches 20 are permitted to swing rearwardly whenever the link 25 is moved in that direction, but if it be desired that only negative totals be printed in red, means is provided to prevent the latches 20 from swinging rearwardly except when a negative total is to be taken. This means comprises a detent 34 pivoted in the machine frame at 35 and having a lug or shoulder 36 to lie in the path of a surface or projection 31 on the right-hand latch 20. Below said surface 31 the latch 20 is shaped to permit the latch to move without interference from the shoulder 36. The latch 34 has a pin-and-slot connection with a link 38. The rear end of the link 38 is guided in the machine frame at 39. The forward end of said link is pivoted at 40 to an arm 4| which is mounted to swing on the axis 28. Rigid with the arm 4| is an arm 42 that underlies a projection 43 on the stem of the total key 44. The arm 42 also underlies a pin 45 on the stem of the subtotal key 46.

When an item is to be subtracted, the subtraction key 30 is depressed, thereby swinging the lever 21 downwardly and pushing the link 25 rearwar/dly. The latches 20 are prevented by the detent 34 from moving rearwardly with the link 25, the spring 3| yielding as said link is pushed rearwardly. Consequently, the members 9 remain in position to present the upper or blue eld of the ribbon to the printing devices. It will be understood that the operation of the latches 20 will be the same as just described if tlie link 25 be moved rearwardly by, the carriage-controlled mechanism disclosed in the before-mentioned French patent.

If a negative total is to be taken, either through manual depression of the total key 44 or the subtotal key 46, or through automatic operation of the carriage controlled mechanism for taking totals disclosed in the before-mentioned French patent, the link 38 is moved forward to swing the latch 34 down out of the path f the surface 31 on the right-hand latch 20, thus permitting'the latches 20 to swing rearwardly when the link 25 is moved rearwardly and thus moving the shoulders 23 out of the path of the lugs |9 and placing the shoulders 24 in thepath of said lugs, whereby in the operation of positioning the type bars 3 for the printing of the total the pins |2 engage the projections I5 and lift the members 9 into position to present the lower or red field of the ribbon to the printing devices. The negative total is thus printed in a color contrasting from that of the items.

If it be desired to print subtracted items as well as negative totals in red, the detent 34 may be omitted.

I claim as my invention:

l. In a machine of the class described, the combination of printing means, a bichrome ribbon, a member for positioning the ribbon, two projections on said member, a part reciprocable in every cycleof operation of the machine and arranged to engage said projections at the ends of its oscillation, a lug on said member, a latch to engage said lug, said latch having two positions, subtraction mechanism to which said latch is yieldingly connected to eiect movement of said latch into either of its positions, a latch for normally preventing the rst-mentioned latch from being moved, and total-taking means for rendering the second latch ineiective.

2. In a machine of the class described, the combination of printing means, a bichrome ribbon, yieldable means for positioning the ribbon, a latch movable to two positions, in one of which positions said latch acts to render said yieldable means ineiective, subtraction mechanism to which said latch is yieldingly connected to effect movement of said latch into either of its positions, a second latch for normally preventing the rst-mentioned latch from being moved, and total-taking means for rendering the second latch ineiective.

3. In a machine of the class described, the combination of reciprocable printing means, a bichrome ribbon, means to move said printing means into and out of printing/position, yieldable means actuated by said last'mentioned means for positioning the ribbon, a latch to restrain said yieldable means, said latch having two positions, and subtraction mechanism to which said latch is connected to eiect movement of said latch into either of its positions.

4.' In a machine of the class described, the combination of reciprocable printing type bars, a bichrome ribbon, a member for positioning the ribbon, two projections on said member, a part reciprocable in every cycle of operations of the machine to restore said type bars to normal position, said last mentioned part being operable to actuate said ribbon positioning member, a -lug on said member, a latch to engage said lug, said latch having two positions, subtraction mechanismto which said latch is universally connected to eiect movement of said latch into either of its positions, a latch for normally preventing the first mentioned latch from being moved and total-taking means for rendering the second latch ineffective.

5. In a machine of the class described, the combination of type bars, a ribbon having more than one color eld, a member for positioning said ribbon, said member acting normally to present a certain eld of the ribbon for coaction with said type bars, means to move said type bars into printing position, and means to restore said type bars to normal position, said last mentioned means being effective to actuate said positioning member to present a certain field of the ribbon when credit imprints are made and means to defeat operation of said member when debit imprints are to be made.

6. In a machine of the class described, the combination of printing means, a bichrome ribbon,

means for positioning the ribbon for coaction with,

the printing means, said positioning means acting normally to present a certain field of the ribbon when debit imprints are to be made, subtraction mechanism, total-taking mechanism, yieldable controlling means actuated by said subtraction mechanismto present the second field of said ribbon and a latch normally disabling said yieldable controlling means and positively actuated by said total-taking mechanism to render said yieldable controlling means elective.

Y 7. In a machine of the class described, the combination of printing means, a. bichrome ribbon, a member for positioning the ribbon, a part reciprocable in every cycle of the machine identied with a printing operation to restore said printing means to normal position, means providing a yieldable connection between said ribbon positioning member and said part, a lug on said member, a latch to engage said lug, said latch being adapted to cooperate with said lug to define variable extents of movement or said member, subtraction mechanism yieldinsly connected to said latch to eilect movement thereof, a second latch for normally preventing the first mentioned latch from being moved and total-taking mns for rendering the second latch ineilective.

8. In a machine of the class described, the combination oi' printing means, a bichrome ribbon, a

member for positioning the ribbon, a part reciprocable in every cycle oi' the machine identiiied with a printing operation to restore said printing means to normal position, means providing a yieldable connection between said ribbon positioning member and said part, a latch to restrain said member to deiine variable extents or movement thereof, subtraction mechanism yieldingly connected to said latch to effect movement thereof, a second latch for normally preventing the first mentioned latch from being moved and totaltaking means for rendering the second latch ineiiective.

WALTER A. ANDERSON. 

